1. Field of the Invention
The present invention relates to a seal imprint verifying apparatus for verifying a target seal imprint such as a representative""s seal or signature seal stamped on marketable securities such as bills or checks by collating the target seal imprint with registered reference seal imprints.
2. Description of the Related Art
In recent years, financial institutions such as banks have constructed on host computers data bases in which information regarding customers are stored and have formed networks by connecting the host computers to terminal apparatuses placed at window counters using communication lines.
When a customer brings a bill or a check to a window counter, an operator conducts the following verifying work for determining if a representative""s seal or a signature seal stamped on the bill or the check is the appropriate one.
That is, the operator uses a terminal apparatus placed at the window counter with , for example, an account number as a retrieval key to retrieve an image data of a reference seal imprint of the corresponding representative""s seal or signature seal from a data base. If a corresponding image data has been already registered, the image of an seal imprint based on the image data is then displayed on the display of the terminal apparatus.
A CRT (cathode ray-tube) or an LCD (liquid crystal display) with high resolution is used as the display of a terminal apparatus to display the image of an seal imprint is displayed in its life-size. The operator then determines if the stamped seal imprint is the appropriate one by verifying the reference seal imprint displayed on the display and a target seal imprint stamped on the real bill or check.
However, the above-mentioned verifying work takes a long period of time because almost the entire work depends on the operator. In addition, occurrences of careless mistakes have been inevitable as long as the verifying work is conducted manually.
Although it is obvious that the efficiency of the verifying work increases if the above-mentioned verifying work is automated using computers and various proposals have been made in the past, any of the proposals had low accuracy of verification and has not been made practicable. The following three major problems has been preventing the practical use of an automated verification:
A first problem is that it is difficult to extract only the portion of an imprint from the image of an object such as a bill.
A second problem is the existence of a partial seal imprint. Since it is impossible for a person to always stamp a seal under a regular condition, a partial seal imprint is formed with a part of a seal imprint lacking in some cases. When the partial seal imprint is collated as a target seal imprint with a complete reference seal imprint, the verification results disagreement even if both seal imprints are derived from the identical seal.
A third problem is the existence of an external frame on a seal imprint. In general, a seal imprint is provided with a square or a circle external frame surrounding a letter portion in the center, and if an external frame of a target seal imprint and that of a reference seal imprint are similar, the agreement of the external frame is overemphasized at a verification, which tends to make a slight difference of the letter portion inside overlooked.
The present invention has been made in view of the above described circumstances, and therefore, a first object of the present invention is to solve the above-mentioned first problem and to provide a seal imprint verifying apparatus which can extract only a portion of a target seal imprint from the image of an object such as a bill and verify it with a reference seal imprint.
A second object of the present invention is to solve the above-mentioned second problem and to provide a seal imprint verifying apparatus which can collate a target seal imprint with a reference seal imprint with high accuracy even if a seal imprint is partially stamped on a bill, etc.
A third object of the present invention is to solve the above-mentioned third problem and to provide a seal imprint verifying apparatus which can collate a letter portion inside a seal imprint accurately irrespective of the similarity of an external frame even in case of a seal imprint small in size.
A first aspect of the present invention is characterized in that a target seal imprint being a seal imprint stamped on an object to be sealed is identified by its color and size and extracted in order to attain the above-mentioned first object of the present invention.
That is, according to the first aspect of the present invention, a seal print verifying apparatus for verifying a target seal imprint stamped on an object is characterized by comprising: an image data capturing means for capturing image data of a target surface on which the target seal imprint is stamped; a color information extracting means for extracting image data having the color of the target seal imprint from the image data of the target surface; a size information extracting means for extracting image data recognized as having the size equivalent to that of the reference seal imprint out of the image data extracted by the color information extracting means; and a determining means for comparing the image data of the reference seal imprint and the image data of the target seal imprint extracted by the size information extracting means to determine whether the target seal imprint does agree with the reference seal imprint.
According to the above construction, when the image data capturing means captures image data of the target surface, the color information extracting means extracts only the image data having the same color as the seal imprint out of the image data of the target surface. The size information extracting means subsequently extracts image data of the target seal imprint out of the results of extraction by the color information extracting means and thereafter can determine whether the target seal imprint agrees with the reference seal imprint by comparing image data.
An object to be sealed is for example a marketable security such as a bill or a check. In addition, an image data capturing means may be an image reader (image scanner). Further, a color information extracting means and a size information extracting means may be the function of a computer program.
The above-mentioned determining means is preferably constructed so as to detect the degree of difference for the plurality of times by changing the direction of either one of the image data of the reference seal imprint or the image data of the target seal imprint. If the minimum value of the acquired plurality of degrees of difference is within the predetermined threshold value, the determining means determines that the target seal imprint agrees with the reference seal imprint.
A second aspect of the present invention is characterized in that a mask is formed to be equivalent to the external shape of a target partial seal imprint stamped on an object and an image formed by the logical product of the mask and the image data of the reference seal imprint are compared and collated with the target seal imprint in order to attain the above-mentioned second object of the present invention.
That is, according to the second aspect of the present invention, a seal imprint verifying apparatus is characterized by comprising: an image data capturing means for capturing image data of the target surface on which the target seal imprint is stamped; a target specifying means for extracting image data of the target seal imprint out of the image data of the target surface; a mask image preparing means for preparing mask image data representing the external shape of the image data of the target seal imprint; an image data composing means for calculating the logical product of the image data of the reference seal imprint and the mask image data to prepare composed reference image data; and a determining means for comparing the composed reference image data and the image data of the target seal imprint to determine whether the target seal imprint agrees with the reference seal imprint.
According to the above-mentioned structure, the image data composing means prepares the composed reference image data being the image data of the reference seal imprint having the external shape of the target seal imprint. Therefore, even if the target seal imprint is in such a condition that a part of the seal imprint is cut out due to partial seal, the system can determine that both seal imprints agree with each other when the both seal imprints are formed by the identical seal.
The above-mentioned determining means is preferably constructed so as to detect the degree of difference for the plurality of times by changing the direction of letters of either one of the image data of the composed reference seal imprint or the image data of the target seal imprint. If the minimum value of the acquired plurality of degrees of difference is within the predetermined threshold value, the determining means determines that the target seal imprint agrees with the reference seal imprint.
If the determining means then changes the direction of letters of the composed reference image data to detect the degree of difference, the image data composing means preferably changes the direction of letters of the reference seal imprint each time the direction is changed by the determining means to prepare the composed reference image data.
A third aspect of the preset invention is characterized in that the external frames of a target seal imprint and a reference seal imprint are removed before comparing both seal imprints in order to attain the above-mentioned third object.
That is, according to the third aspect of the present invention, a seal imprint verifying apparatus is characterized by comprising: an image data capturing means for capturing image data of the target surface on which the target seal imprint is stamped; a target specifying means for extracting image data of the target seal imprint out of the image data of the target surface; an external frame removing means for preparing image data of the target seal imprint of which external frame portion is removed therefrom, and preparing image data of the reference seal imprint of which external frame portion is removed therefrom; and a determining means for comparing the reference seal imprint and the target seal imprint after the external frame portions are removed by the external frame removing means to determine if both seal imprints agree with each other.
According to the above-mentioned construction, image data of the target seal imprint and the reference seal imprint of which external frame portions are removed therefrom are prepared. Then, since these images are compared, the accuracy of the result of determining agreement or disagreement of both image data is improved over the case in which the reference seal imprint and the target seal imprint are simply compared.
Further, before the process by the external frame removing means, it is possible to determine by an external diameter determining means whether the external diameter of the target seal imprint agrees with the external diameter of the reference seal imprint and to determine by an external shape determining means whether the external shape of the target seal imprint agrees with the external shape of the reference seal imprint. In this case, the external frame removing means may be made as preparing an image data excluding the external frame of the seal imprint only when the outside diameters and the external shapes are recognized as agreeing with each other by the outside diameter determining means and the external shape determining means, respectively.
Incidentally, even in case that the process as described above is gone through, agreement/disagreement cannot be determined in some cases. In such a case, determination is eventually made by an operator. A fourth aspect of the present invention is aimed to provide an apparatus capable of conducting verification easier than before by supporting verifying work when an operator conducts verification.
According to the fourth aspect of the present invention, a seal imprint verifying apparatus for displaying on a display apparatus a target seal imprint stamped on an object to be sealed and a reference seal imprint registered in advance and verifying them to find if they agree with each other is characterized by comprising: an image data capturing means for capturing image data of the target surface on which the target seal imprint is stamped; a target specifying means for extracting image data of the target seal imprint out of the image data of target surface; and a display controlling means for alternatively displaying either two of an image data of the target seal imprint, an image data of the reference seal imprint or a transparent image data overlapping both seal imprints on the identical area on the display apparatus.
According to the above-mentioned construction, overlapping work of the seal imprints can be conducted inside the seal imprint verifying apparatus without using an actual object such as a bill.
The above-mentioned display controlling means displays the image data of the reference seal imprint for a first period of time and displays the transparent image data for a second period of time, thereby being capable of alternatively display these image data. In this case, the first and the second periods of time can be arbitrary set by an operator.
Further, the display controlling means displays an image data of the reference seal imprint for a first period of time, displays an image data of the target seal imprint for a third period of time after a non-displaying period for a second period of time, places a non-displaying period for a fourth period of time, thereby being capable of alternatively displaying these image data with the non-displaying period in between. In this case, the first, the second, the third and the fourth periods of time can be arranged as arbitrary set by an operator.